AD7680 Analog Devices, AD7680 Datasheet
AD7680
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AD7680 Summary of contents
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... Remote data acquisition systems High speed modems Optical sensors GENERAL DESCRIPTION The AD7680 is a 16-bit, fast, low power, successive approximation ADC. The part operates from a single 2 5.5 V power supply and features throughput rates up to 100 kSPS. The part contains a low noise, wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 7 MHz ...
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... Terminology ...................................................................................... 9 Typical Performance Characteristics ........................................... 10 Circuit Information ........................................................................ 12 Converter Operation .................................................................. 12 Analog Input ............................................................................... 12 ADC Transfer Function ................................................................. 13 REVISION HISTORY 5/11—Rev Rev. A Deleted the Evaluating the AD7680 Performance Section ...... 19 Changes to Ordering Guide .......................................................... 21 1/04—Revision 0: Initial Version Typical Connection Diagram ................................................... 13 Digital Inputs .......................................................................... 13 Modes of Operation ....................................................................... 14 ...
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... V min/V max 5.2 mA max 4.8 mA max 0.5 μA max 26.4 mW max 2.75 μW max Rev Page AD7680 = unless otherwise noted A MIN MAX Test Conditions/Comments kHz sine wave IN @ − −0.1 dB Typically 10 nA 200 μA ...
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... AD7680 1 SPECIFICATIONS Table 2 4.096 2.5 MHz SCLK Parameter DYNAMIC PERFORMANCE 2 Signal-to-Noise + Distortion (SINAD) 2 Signal-to-Noise Ratio (SNR) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) 2 Intermodulation Distortion (IMD) Second-Order Terms Third-Order Terms Aperture Delay Aperture Jitter ...
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... Rev Page AD7680 Test Conditions/Comments Digital I/ SCLK on or off 4.096 V DD SCLK on or off 3 100 kSPS 4.096 V; 1.75 mA typ SAMPLE 100 kSPS 3.6 V; 1.29 mA typ SAMPLE ...
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... AD7680 TIMING SPECIFICATIONS Table 2 5 MIN Limit MIN MAX Parameter 250 250 SCLK 2.5 2 × × t CONVERT SCLK SCLK t 100 100 QUIET 120 0 SCLK ...
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... 0.3 V maximum rating conditions for extended periods may affect DD 1 ±10 mA device reliability. −40°C to +85°C −65°C to +150°C 150°C 450 mW 229.6°C/W 91.99°C/W 450 mW 205.9°C/W 43.74°C/W 215°C 220° Rev Page AD7680 ...
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... SDATA Data Out. Logic output. The conversion result from the AD7680 is provided on this output as a serial data stream. The bits are clocked out on the falling edge of the SCLK input. The data stream from the AD7680 consists of four leading zeros followed by 16 bits of conversion data that are provided MSB first ...
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... The AD7680 is tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. In this case, the second-order terms are usually distanced in frequency from the original sine waves, while the third-order terms are usually at a frequency close to the input frequencies ...
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... AD7680 TYPICAL PERFORMANCE CHARACTERISTICS Figure 5 shows a typical FFT plot for the AD7680 at 100 kSPS sample rate and 10 kHz input frequency. Figure 6 shows the signal-to-(noise + distortion) ratio performance versus the input frequency for various supply voltages while sampling at 100 kSPS with an SCLK of 2.5 MHz. ...
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... V = 3.0V DD ° TEMP = 25 C 2.0 1.5 1.0 0.5 0 –0.5 –1.0 0 10000 20000 30000 40000 50000 CODE Figure 9. AD7680 Typical INL 1 3.0V DD TEMP = 25 1.0 0.5 0 –0.5 –1.0 –1.5 60000 70000 0 10000 Rev Page AD7680 ° C 20000 30000 40000 50000 60000 70000 CODE Figure 10. AD7680 Typical DNL ...
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... The serial clock input accesses data from the part and also provides the clock source for the successive approximation ADC. The analog input range for the AD7680 external reference is not required for the ADC nor is there a reference on-chip. The reference for the AD7680 is derived from the power supply and thus gives the widest dynamic input range ...
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... INPUT . DD Digital Inputs The digital inputs applied to the AD7680 are not limited by the maximum ratings that limit the analog inputs. Instead, the digital inputs applied can and are not restricted by the V + 0.3 V limit as on the analog inputs. For example, if the ...
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... AD7680 MODES OF OPERATION The mode of operation of the AD7680 is selected by controlling the (logic) state of the CS signal during a conversion. There are two possible modes of operation, normal and power-down. The point at which CS is pulled high after the conversion has been initiated determines whether or not the AD7680 enters power- down mode ...
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... SCLK, regardless of the SCLK frequency, the AD7680 goes back into power-down again. This avoids accidental power-up due to glitches on the CS line or an inadvertent burst of 8 SCLK cycles while CS is low. ...
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... V). If the power-up DD time from power-down is 1 μs, and the remaining conversion time is 8 μs, (using a 20 SCLK transfer), then the AD7680 can be said to dissipate 6.84 mW for 9 μs during each conversion cycle. With a throughput rate of 10 kSPS, the cycle time is 100 μs. ...
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... A minimum of 20 serial clock cycles are required to perform the conversion process and to access data from the AD7680. CS going low provides the first leading zero to be read in by the microcontroller or DSP. The remaining data is then clocked out by subsequent SCLK falling edges beginning with the second leading zero ...
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... FPGAs and ASICs. AD7680 TO ADSP-218x The ADSP-218x family of DSPs can be interfaced directly to the AD7680 without any glue logic required. The SPORT control register should be set up as follows: TFSW = RFSW = 1, Alternate Framing INVRFS = INVTFS = 1, Active Low Frame Signal ...
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... A minimum etch technique is generally best for ground planes, because it gives the best shielding. Digital and analog ground planes should be joined at only one place. If the AD7680 system where multiple devices require an AGND to DGND connection, the connection should still be made at one point only, a star ground point that should be established as close as possible to the AD7680 ...
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... AD7680 OUTLINE DIMENSIONS INDICATOR 1.30 1.15 0.90 0.15 MAX 0.05 MIN Figure 23. 6-Lead Small Outline Transistor Package [SOT-23] (RJ-6) Dimensions shown in millimeters Figure 24. 8-Lead Micro Small Outline Package [MSOP] (RM-8) Dimensions shown in millimeters 3.00 2.90 2. 3.00 1.70 2.80 1.60 2.60 1. PIN 1 0.95 BSC 1.90 BSC 0.20 MAX 1.45 MAX 0.08 MIN 0.95 MIN SEATING 0.50 MAX PLANE 0.30 MIN COMPLIANT TO JEDEC STANDARDS MO-178-AB 3 ...
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... AD7680BRJZ-R2 −40°C to +85°C AD7680BRJZ-REEL7 −40°C to +85°C AD7680BRM −40°C to +85°C AD7680BRM-REEL −40°C to +85°C AD7680BRM-REEL7 −40°C to +85°C AD7680BRMZ −40°C to +85°C AD7680BRMZ-REEL −40°C to +85°C AD7680BRMZ-REEL7 −40°C to +85° RoHS Compliant Part ...
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... AD7680 NOTES Rev Page ...
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... NOTES Rev Page AD7680 ...
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... AD7680 NOTES © 2004-2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03643-0-5/11(A) Rev Page ...